The present invention relates generally to side impact warning systems, and more particularly, to a method and apparatus for detecting a side impact collision and deploying a device in response thereto.
Collision warning and countermeasure systems are desirable features in an automotive vehicle. Collision warning systems provide the vehicle operator knowledge and awareness of objects or vehicles within a close proximity so as to prevent colliding with those objects or provide the activation of a safety system.
Collision warning systems and countermeasure systems exist in various forms. Certain collision warning systems and countermeasure systems are able to sense a vehicle or object in close proximity to a host vehicle and warn the host vehicle operator, such that the operator can take precautionary steps to prevent collision or injury. Other collision warning systems and countermeasure systems activate passive or active countermeasures such as airbags, load limiting seatbelts, or brake control whereby the system itself aids in preventing a collision.
One way in which to track an object is to use radar. Radar can provide the relative closing speed of an object to the vehicle. One problem with such a device in a side impact system is that the radar may misreport or misclassify an object due to the vehicle slipping sideways (side slip). Because of side slip, the relative velocity for an object may be changed. In a typical system, stationary and low closing rate objects within the sensor scan are sorted and not reported as threatening. Higher closing rate objects are reported and tracked and can become threatening if the system predicts collision of the vehicle with the objects. When vehicle slide slip occurs, non-moving objects may be misreported or misclassified. That is, a stationary object may become a moving object relative to the vehicle. Likewise, object tracking errors and slower system processing time may result from the side slip.
Therefore, it would be desirable to provide an improvement in the detection of a side impact from an object.